Boiler-furnace



(No Model.)

E.' W. VANDUZBN. BOILER PURNAGB.

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A WMMMMWM tion ofthe bottom ot' the furnace under the' UNITED STATES PATENT GEEICE.

EZEA wQvtANDUzEN, oF NEwPoET, KENTUCKY.

BOILER-FURNACE.

SPECIFICATION forming-part of Letters Patent No. 270,157, dated January 2, 1883.

` Appuwmnmeattaye,ieee. (nommen by providing a thick bridge-wall at the rear of the grate-bars, through which bridge-wall au arch is sprung, with its bottom iuclining up ward from the grate-bars proper, and the arch itself furnishing a supplemental fire-chamber, through which the products of combustion must pass, and become heated and consumed either in the arch or in the combustion-chamber in the rear thereof. Air is provided by several methods to support combustion in the arch and rear fire-chamber, all of which will be fully explained in the description .of the accoinpanying drawings, making a part ot' this specification.

Figure lis a longitudinal central vertical section embodying my improvement. Fig. 2 is a front elevation Online .1:00, Fig. 1. Fign is a'section on line yg/,"Fig. l. Fig. 4 is a sectional plan of the interior of the bridge-wall on line a: w, Fig. 3. Fig. 5 shows a modificaarch. Fig. 6' is a plan of one form ot' the botber G.

tom of thefuruace underthe arch; Figs. 7 and S, other modilications of the same.

A represents an ordinary boiler; B, the ordinary furnace-chamber; C, the grate-bars,

audi D a cross-piece on which the grate-bars rest.

E represeutsa bridge-wall projecting up to the boiler in rear ofthe grate-bar C. y

G represents au arch sprung from the rear ofthe grate-bars C, and extending through the wall E E', forming a secondary furnace.

H represents the bottom of the arch-cham- It is madeinclining upward from the front ot' the arch for two rea-son: first, to contract the arch at the rear to insureamore peri'ectcombustion of the gases, and, second, to 'keep the area of the arch at its rear the same, so as not to be obstructed by cinders and ashes accumulating iu the rear. is perforated or made with openingsthrough it, and with an air-space, I, underneath to keep Vthe plate from becoming too highly heated,

and to supply air to that part of the combustion-chamber within the arch G where the coked coal is consumed.

I have shown three forms ot bottoms for the furnace within the arch G, one form represented by Hin Figs. 5 and 7. Figs. 4 and 6 show a perforated metal plate used in lieu ot' the bars H, and Fig. S shows ordinary gratebars, which may be used instead of the forms shown in Fig. 5 or 6.

In order to more perfectly supply air to the combustion-chamber,` I make the bridgefwall E hollow or with openings K, which openings communicate with registers L below'the furnace chamber for supplying any desired amount'of air. y

In order to heat the air` before admitting it to the arch-chamber G, I provide brick posts or winding air-passages through the hollow bridge-wall E to check the too rapid passage of the air which enters the arch Gr through openings o on either side of the arch. l

A very important result is obtained by having the bottom `of the arch G inclined upward toward the rear. It prevents the coal and incandescent fuel from working backward to obstruct the iiue. It preserves the tine-area the same and allows the fuel to be stirred, carrying the ashes through the grate, and causes the fuel to incline toward the furnace. By making the bridge-wall E hollowitprevents ateo high heating of the wall forming the arch,

which prevents a too high degree` of heat to the wall and that portion of the boiler over it.

Other forms of making hollow walls each side ofthe arch G may be employed instead of the form here shown. A' steam or air blast maybe employed to increase the draft, it' desired.

S represents orifices pierced in a ledge at the rear of plate or gratebars H to admit air into the rear chamber, M, to furnish oxygen to support combustion.

-I claiml. A boiler'furnace composed substantially of the furnace-chamber B and the secondary furnace G, formed within the arch of the bridge- This grate-surface,

ICO

i l o 279.157

wall, -and provided with the grate-bars H and air-spaces I underneath saidv grate-bars; substantially as described.

2. In a boiler-furnace, a secondary furnace, Gr, formed in the hollow bridge-Wall, which is provided with air-openings e, and the perforated plate or grate bars H, substantially as del scribed.

v3. In a boiler-furnace, the bridge-wall E, provided with the register L and air-passages. e, conveying air into the secondary furnace G, substantially as described.

4. In a boiler-furnace, the combination of the furnace B, the grate, the bridge-Wall at the rear of the grate, constructed with the arched v5 chamber G, the grate H, forming a bottom to the arched chamber, which inclines upward from front to rear, the perforated ledge under the rear elevated end ofthe grate H, and the air-space `I under the lutter,`su'bstantiully as 2o described.

In testimony whereofl have hereunto set my hand in the presence ot' two` subscribing Wit'- `messes.

EZRA NV. VANDUZEN.

Witnesses:

JNO. E. JONES, J. H. CHARLES SMITH. 

